UNSUCCESSFUL TESTING METHODS

Shape FactorShape factor is the ratio of projected fiber length over total length. Shape factor testing ended due to time restrictions and large possibility for human error. The relatively small sample size (100 fibers versus thousands in the automated system) and possibility of bias when picking measured fibers made the test unreliable.

Kappa Number Kappa number is a titration used to determine amount of lignin in the pulp. The blank solution kept forming a precipitate that clouded the mixture. Only one successful Kappa number test was performed. The reason for the precipitation is unknown but was suspected to be the solution pH.

Handsheet TestingHandsheets are formed from pulp using a British Sheet Mold machine to evenly mix a dilute pulp sample and dewater it to form a sheet. The pulp received contained significant wood fiber (shives). This made the handsheettexture and consistency notably rougher than the mill-made samples. Handsheet quality and GP kraft paper were not comparable, likely due to additional processing the pulp receives at the mill during paper manufacture.

RESULTS

The following graphs are some of the results found from pulp and paper testing. Many comparisons showed no relationship or confusing trends.Why and how are we correlating

strength metrics?

Pulp is wood mass that has been broken down by

chemical or mechanical processes. Determining pulp

characteristics helps Georgia-Pacific decide what steps

to take in order to produce the best quality paper.

“Good” or “bad” paper results may be attributed to the

quality of pulp entering the process.

The OSU Pulp Metrics Team performed the following tests to determine relationships between pulp and paper strength for GP.

Pulp Testing1. Canadian Standard Freeness (CSF) Test

Determines drainability of the pulp2. Kappa Number Test

Determines amount of lignin in the pulp3. Zero-Span Tensile Strength Test

Determines strength of individual fibers (FS)Determines length of fibers (L)Determines bonding of fibers (B)

4. Shape Factor TestDetermines amount of deformation in the fibers

Paper Testing1. Burst Test

Determines pressure where paper “bursts”2. Densometer Test

Determines porosity of paper3. Fold Test

Determines fold endurance of the paper4. Tear Test

Determines tear resistance of the paper

Background

Suggested Future Work

• Additional zero-span tensile tests (FS, L, B & PQI)

• Automated shape factor analysis (MATLAB)

• Test Kappa side reactions/precipitations

• Analysis of GP’s Ring Crush and Concora compared

to OSU paper testing methods

• Discontinue CSF testing

• Explore processing parameters between the

pulp and the finished paper : pressure (P),

temperature (T), relative humidity (RH),

residence time (t), and others.

• Source pulp nearer to the papermaking entry

• Explore fiber flexibility, bonding properties

Acknowledgements:

Casey Kramer (Sponsor)David Smith (Mentor)Andy Brickman (Instrument Technologist)Dr. Kaichang Li (Laboratory Owner)Jian Huang (Laboratory Manager)Dr. Philip Harding (Project Coordinator)

References:1. News and Awards. Georgia-Pacific. 4/26/13. Web. Accessed 5/12/14.

http://www.gppackaging.com/Pages/News/News-and-Awards.aspx2. Karlsson, H. Fibre Guide. Lorentzen & Wettre. Sweden. 2006. Print.

Figure 4: The figure shows little variance in the values of CSF collected. The lack in variation and overlapping of error bars indicates that no trend exists between CSF and tear force.

Figure 3: Length of fibers versus densometer time. This suggests that increased length of fibers increases the density (decreases porosity) of the paper. This goes against the assumption that longer fibers for the same paper mass produce more paper pores.

Figure 2: The above graph shows length versus fold endurance. It shows that fold endurance is not dependent upon length of fibers.

Figure 1: The above graph is fiber strength versus burst pressure. It shows that burst pressure is not dependent upon fiber strength.

The figures above have few data points to draw conclusions from and small ranges in pulp metric values. This makes it difficult to validate the trends observed. The overwhelming results suggest that additional testing needs to be performed to validate trends that surfaced in fiber strength, length and bonding measurements. The error bars represent a 95% confidence interval.

Some variation is possible in paper testing. Test results can be skewed by local structure and fiber orientation differences as well as humidity and temperature in the lab.

This CSF method does not simulate the drainage process in a modern paper machine.2 CSF does not show a correlation to paper quality due to a lack of range of CSF values with varying paper quality.

CORRELATING PULP QUALITY METRICS TO PAPER MACHINE PERFORMANCEMary Isham, Steph Walker, Hui Yan, Philip Harding, Casey Kramer

Corrugated Kraft1

Circular handsheet formed

Pulp from washer

0.3 wt % dilution

Pressure clamp

Fiber with shives

College of Engineering Chemical, Biological & Environmental Engineering

Bad handsheets

Pulp/

Paper

1

Pulp/

Paper

2

Pulp/

Paper

3

Pulp/

Paper

4

Pulp/

Paper

5

CSF ✓ ✓ ✓ ✓ ✓

Kappa ☓ ☓ ☓ ☓ ☓

Shape Factor ✓ ✓ ☓ ☓ ☓

Zero-Span ✓ ✓ ✓ ☓ ☓

Fold ✓ ✓ ✓ ✓ ✓

Tear ✓ ✓ ✓ ✓ ✓

Burst ✓ ✓ ✓ ✓ ✓

Densometer ✓ ✓ ✓ ✓ ✓

Totals

The team has completed the following tests.

2,000

2,200

2,400

2,600

2,800

3,000

3,200

3,400

3,600

30 32 34 36

Bu

rst

[psi

*cm

2/g

]

FS [N/cm]

60

80

100

120

140

160

180

200

0.40 0.45 0.50 0.55

Fold

[cm

2/g

]

L [%]

1,000

1,500

2,000

2,500

3,000

3,500

0.40 0.45 0.50 0.55

Den

som

eter

[s*

cm2/g

]

L [%]

50

60

70

80

90

100

110

760 780 800 820

Tea

r [N

*cm

2/g

]

CSF (mL)